1. Field of Invention
The present invention relates to power converters, and more particularly to, a power converter using a single, tapped transformer for multiple ranges of input voltage.
2. Description of Related Art
Power converters are essential for many modern electronic devices. Among other capabilities, power converters can adjust voltage level downward (buck converter) or adjust voltage level upward (boost converter). Power converters may also convert from alternating current (AC) power to direct current (DC) power, or vice versa. Power converters are typically implemented using one or more switching devices, such as transistors, which are turned on and off to deliver power to the output of the converter. Control circuitry is provided to regulate the turning on and off of the switching devices, and thus, these converters are known as “switching regulators” or “switching converters.” The power converters may also include one or more capacitors or inductors for alternately storing and outputting energy.
In some applications, there may be a multiple ranges of input voltages (i.e., high voltage and low voltage) for a power converter. This may be the case, for example, in some consumer electronic equipment which can be powered from wall outlets (i.e., AC mains voltages) or powered by automotive voltages. According to previously developed techniques, two completely separate power systems—each having its own transformer, controller, and switching elements—were provided for such applications in order to accommodate the multiple (e.g., dual) ranges of input voltages. This increases the costs for implementing the power conversion functionality and requires additional space in the electronic equipment, which can be a premium for some especially small and portable devices.